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From Hampton Roads to Spithead

The U.S. Navy’s fleet of monitors was built to root out Confederate warships guarding the Southern coastline—so the story goes. But a crucially overlooked factor in the meteoric rise of the Union ironclad navy was the need to guard the American coastline from British intervention in the Civil War.

‘The effect was very grand,” wrote a London Times reporter, “as the vast globe of metal propelled from the mouth of the gun with a deep hoarse roar went hurtling towards on its course until it fell at an estimated distance of about 3,500 yards from the ship.” It was Friday afternoon, 29 June 1866 at Spithead, outside the naval base and arsenal of Portsmouth—the strategic heart of British sea power. The double-turreted U.S. ironclad monitor Miantonomoh , en route to Russia on a goodwill mission, had just fired a demonstration shot from one of her four tremendous 15-inch guns for members of the press and Parliament and the Lords of the Admiralty, who were on board, as well as interested observers crowded along the shore.

“The second gun was charged with 35 lbs. powder, a solid iron shot of 460 lb., and fired point blank,” the reporter continued. “If the last shot was grand, as exhibiting the flight of a 15-inch shell, this was more interesting, as exhibiting—what we have as yet made no provision for in rifling our heavy naval artillery—the perfection of ricochet firing. The immense ball spun along its course over the surface of the water as truly as the cricketer’s ball passes over the smooth green sward towards the wicket.” 1

Turning to his guests, Assistant Secretary of the Navy Gustavus Vasa Fox, the senior U.S. official on board, responded to their quibbling by stating that “if the experiment could be made without exciting ill-feeling on either side,” he would allow “the whole ironclad fleet of England to open fire on the Miantonomoh , and continue it for two days, provided that the Miantonomoh might afterwards be allowed to have ten hours’ firing at [British] ships in return.” 2

There was an awkward moment of silence. Controller of the Royal Navy Rear Admiral Robert Spencer Robinson furtively glanced at the tight-lipped Duke of Somerset, the First Lord of the Admiralty, who in turn could not meet the burning gaze of Captain Cowper Phipps Coles, Britain’s outspoken turret-ship advocate and bitter opponent of the British navy’s faith in broadside ironclads.

The Times reporter meanwhile licked his lips and smiled. This was great press. With a wink, Fox had just challenged Queen Victoria’s navy to a polite trial by fire, a rival show of strength to replace years of taunts—and threats—on both sides of the Atlantic with actual deeds. The Lords of the Admiralty had to admire the pluck, the impertinent frankness. But standing on the metal deck plates of this Yankee war machine, feeling the whole thing vibrate from the engines, watching the wisps of white smoke drift off from the colossal gun protected by ten inches of turret armor, Fox’s suggestion wasn’t really very funny at all.

As there was currently no response possible on the part of the British navy, the topic was quickly changed. It was bad enough that a U.S. monitor prove capable of crossing the Atlantic divide in the first place. American ironclads weren’t supposed to be able to do that. And while critics could point to the ship’s lack of coal bunkerage, resulting in her needing a tow much of the way, neither did the “diving bell” sink like an iron coffin, as did the original Monitor . Instead she rolled no more than 7 degrees while her two paddle-wheeled escorts labored at up to 24. “Her officers consider it a perfect success,” noted one reporter from Britain’s reputable Mechanics’ Magazine , “and taking the broad fact as it stands, we do not see how the conclusion is to be avoided.”

The Miantonomoh ’s visit, as one British journal later recalled, was “a most friendly act when it can be looked on philosophically.” Nothing was hidden; every part of the vessel and her armament was open for inspection “by persons who knew well how to set a proper value on the powers of the monitor.” Command of the sea no longer belonged to lofty sailing men-of-war—wood or iron, armored or not—but started afresh with these “bulldogs of the sea.” 3

After 150 years, this relatively forgotten story needs retelling. The history of the Union Navy’s ironclad program during the Civil War years is not simply about the “ Monitor vs. the Merrimac ,” gunboats vs. forts along the Mississippi, the siege of Charleston, the Battle of Mobile Bay, or the assault on Fort Fisher. Too much of its focus remains acutely nearsighted, too parochially American for its own good, when naval history is rarely if ever one-sided or isolationist.

The oceans that braced the Union during the Civil War were protective moats as well as highways for intervention, if not invasion. Months before the Navy Department worried over the conversion of the wooden steam frigate Merrimack ’s scuttled wreck into the fearsome iron-plated CSS Virginia , it had to contend with Scientific American ’s warning that “a whole fleet of unplated vessels are completely at the mercy of one of the new iron-plated ships,” and that presently, “we have not a single first class war steamer—one that can compete with the most recently built French and British ones . . . we mean the iron-cased war wolves.”

The launching of Britain’s first ironclad champion, HMS Warrior , was full-page news in Harper’s Weekly on 9 February 1861 (five days after the Confederate States of America had been announced). The “Revolution in Naval Warfare—Shot-Proof Iron Steamships” was considered as ominous as the political revolution under way at home. 4

But what shape would the Union’s own ironclad program take? No one expected to outbuild the European powers, namely Great Britain and France, in terms of gigantic world-ranging steam-powered broadside ironclads. Rarely was the U.S. Navy concerned with like-for-like naval-arms races. Instead, a tradition had been proudly developed of better-made, better-manned, and technologically superior warships that might better even the odds. 5

The ensuing Civil War was predominantly a brown-water affair whose chief strategic lines of communication, supply, and invasion were along a generally shallow, treacherous coastline, and up and down winding rivers. This alone led to a plethora of armored steamship designs, some brilliant, others disastrous.

The efforts of James B. Eads and Samuel Pook, for example, resulted in the seven City-, or Cairo -, class semi-armored Union gunboats for combined operations along the Western rivers. Their slanted casemates withstood most Rebel fire, but compromises in design, namely the ability to draw only six feet of water, meant that the aft casemates, decks, and hulls were unprotected, leaving them vulnerable to attack from behind, above, and below. Consequently, on 17 June 1862, most of the crew of the Mound City was scalded to death when a plunging shot from shore batteries along Arkansas’ White River penetrated her steam drum. A month later, the Carondelet was disabled by the Confederate ram Arkansas firing on her stern during a running battle above Vicksburg, while the Cairo quickly sank on 12 December after striking a mine (or torpedo, as they were then known as) in the Yazoo River.

Other Union casemate ironclads such as the Choctaw and Lafayette were overweight converted merchant paddle-steamers haphazardly armed and armored and intended for ramming as well as engaging forts. This was laughable since they could barely fight the current and steered badly. But however bizarre Northern river ironclads appeared and performed, they were nevertheless able to overwhelm the comparable naval resources of the Confederacy.

The Union blockade along the coast was a different matter inasmuch as naval blockades and maritime wars typically involve neutral powers. In this case, especially, Great Britain was an overriding worry for President Abraham Lincoln’s government and a beacon of hope for Confederate leaders. Indeed, cotton was only king if the British could be induced—or compelled—to intervene in the Civil War, and certainly the prospect at times was tempting. By the mid-19th century, the nature of the new global economy meant that a war over the fate of America affected everyone’s interests. The transatlantic trading relationship was the most lucrative in the world, in history even. And while Queen Victoria’s own Proclamation of Neutrality angered many Northerners who expected moral support from Britain if nothing else, the blockade would take months, if not years, to be considered legally effective as far as foreign powers were concerned.

So not only did the Union Navy need to prosecute the war along the Southern coastline, it needed to protect the blockade from Confederate ironclad challenges from within and far more serious (though prospective) European threats from without. This also led to ironclad design challenges—ultimately culminating in the original Monitor and her increasingly ambitious follow-ons such as the Miantonomoh . That such light-draft, low-freeboard, heavily armored, and turret-armed ironclads came to dominate the U.S. Navy for a generation speaks to the international dynamic of the Civil War as well as its domestic front.

The numbers themselves are revealing. Of the 82 armored warships laid down in the Northern states, 61 (74 percent) were turreted. Nine of these (15 percent of the turreted vessels) were specifically for river service, while the 20 rather notorious ultralight-draft monitors were intended more for river and inner-coastal operations. The remaining 51 percent of the turreted vessels (38 percent of the total number of ironclads laid down by the North during the Civil War) therefore consisted of

• Two John Ericsson–designed monster oceangoing monitors, the Dictator and Puritan

• Four Navy-designed double-turreted Monadnock -class monitors

• Four huge oceangoing Kalamazoo -class follow-ons.

Perhaps a more revealing statistic is that only 48 (roughly 59 percent) of the Union ironclads laid down during the Civil War were actually completed before the conflict ended. Of the 48 vessels, 30 were turreted, and 10 of these were for river or inner-coastal service. Though the Puritan was launched in July 1864, work was suspended, and she was never completed; the four Kalamazoos were broken up on the stocks, yet the four monitors of the Monadnock -class, including the Miantonomoh , were all commissioned before the end of 1865, as well as 14 of the 20 ultralight drafts.

Another significant point about the turreted vessels, at least, is that all of them except the Kalamazoos were approved before the end of 1862. Therefore the United States may be said to have committed to its ironclad building program, if not the formulation of its naval strategy, by the same date. Considering that the U.S. government had not established its first Ironclad Board to review design proposals until the summer of 1861, and did not formally contract for John Ericsson’s original Monitor until the beginning of October, this fact stands as an impressive one in the annals of warship design and decision making.

Years before, Ericsson, a Swedish-born inventor-engineer, had devised a “sub-aquatic system of warfare” for the allied powers during the Crimean War. His plan called for a specialized steamer, screw propelled and wholly armored, with only a shallow raft mounting a revolving iron dome visible above the waterline. Inside this “impregnable globe” would be guns of the heaviest-known caliber and capable of inflicting singular knockout blows.

Armed with such a vessel, Ericsson suggested to Emperor Napoleon III, gauntlets could be run with relative safety and “A fleet at anchor might be fired and put in a sinking condition before enabled to get under way.” 6 Bombarded with a stream of plans of how to win the war in a single day, the French kept the idea of iron armor plating and steam propulsion generally and rejected Ericsson specifically.

Under the guidance of their own Ministry of Marine, shallow-draft “batteries” were constructed that could deliver a conventional broadside against shore fortifications at fairly close quarters. At the very least these might suppress counterfire while a general bombardment rattled the defenders and troop landings took them from the rear. Iron might thus neutralize granite. At the 17 October 1855 Battle of Kinburn, the French armored batteries took amazing punishment yet performed well. Ericsson accordingly tucked his proposal away and returned to other ventures.

On 29 August 1861 Ericsson drafted a letter to President Lincoln offering his services. Now the goal was rooting out Confederate warships guarded by land batteries—particularly the remains of the Merrimack , which the Rebels were known to be converting into an armor-plated blockade killer. Ericsson was also canny enough to mention in closing the “now well-established fact that steel clad vessels” could not be stopped by forts, and that New York City was “quite at the mercy of such intruders, and may at any moment be laid in ruins.” If Britain or France ever did challenge the Union blockade and enter the war, Ericsson reminded Lincoln, only his weapon system held the key to “crushing the sides” of their ironclads. 7

Civil War history leaves out this letter; indeed, Ericsson never sent it. Perhaps he sensed that his proposal would be lost in another flood of half-baked ideas from mostly underqualified engineers and inexperienced inventors. Nor could he go the customary route of pitching his plans to Navy professionals; he was in the midst of a long-standing feud with many of them for the disastrous 1844 explosion of the “Peacemaker” cannon on board an innovative screw warship he had designed, the Princeton .

Instead, as the well-told story goes, he was drawn into the public bids for ironclad steamers by Cornelius Bushnell, who wanted the famed engineer to double-check the stability of his own submission. While performing the necessary calculations, Ericsson pulled out the dusty cardboard mock-up of his strange cupola vessel. It was nowhere near as predictable as Bushnell’s soon-to-be ironclad corvette Galena . But his colleague immediately recognized a potential alternative to broadside ironclads—and a deadly response to European powers. On Ericsson’s behalf, Bushnell personally presented the model to Secretary of the Navy Gideon Welles and then to the secretary’s assistant, Gustavus Fox, announcing that the president “need not further worry about foreign interference; I [have] discovered the means of perfect protection.” 8

If this extraordinary turreted man-of-war was first approved and contracted for in the two-tone shadow of a threat—one Confederate and the other European—then it was certainly in the harsh light of the Trent Affair, which began playing out within a fortnight of her keel being laid, that she actually found a name. Nothing roused Britannia’s ire more than the brazen capture of two Confederate emissaries on board the British packet steamer by a Yankee cruiser on 8 November 1861. Anglo-American tensions already had been at the breaking point since the Civil War began; the blockade, the Queen’s Neutrality, the highly protectionist Morrill Tariff, and the apparently open-ended duration of the conflict itself had sparked an increasingly acrimonious press war with Columbia. Each side accused the other of arrogance and ignorance, and both were probably right.

Only one side, though, had the muscle to ram home its point at that precise moment. This was a brutal lesson that Lincoln painfully acknowledged when the United States quietly released the two Confederates back into British custody on 1 January 1862. Far less subtle was Harper’s Weekly in its cartoon of 11 January 1862, which depicted John Bull’s menacing new henchman wearing a suit of armor and labeled “Warrior”—a connotation Prime Minister Lord Palmerston fully supported even before the crisis erupted. In a letter earlier that summer to the First Lord of the Admiralty, Palmerston urged that both the Warrior and her sister ship, the Black Prince , be sent to the American station as soon as they were completed. 9 Yet the unintended side effect of all this realpolitik and deterrence was to sharply focus Union attention on its own need for an ironclad defender.

Immediately after the Trent Affair , in reply to a request from Fox for a suggested name for his warship, Ericsson wrote: “The impregnable and aggressive character of this structure will admonish the leaders of the Southern Rebellion that the batteries on the banks of their rivers will no longer present barriers to the entrance of the Union forces. The iron-clad intruder will thus prove a severe monitor to those leaders.”

He continued:

But there are other leaders who will also be startled and admonished by the booming of the guns from the impregnable iron turret: “Downing Street” will hardly view with indifference this last “Yankee notion,” this monitor. To the Lords of the Admiralty the new craft will be a monitor. . . .

On these and many similar grounds, I propose to name the new battery Monitor. 10

Had the Trent crisis not occurred during this interval, the Union ironclad navy might very well have had a different face, and the Civil War ended differently. It took the much more ominous threat of a potential duel with the Warrior , or a similar European armored warship, to underscore the need for a light-draft, ironclad-killing ironclad with an emphasis on sheer impregnability and hard-hitting “monster” guns—even at the direct expense of long-range sea-keeping or cruising.

The problem was that the Monitor , like all early ironclads, was expected to fulfill a variety of frequently conflicting roles. In her strict capacity as a man-of-war she successfully dominated American coastal waters, starting with the Battle of Hampton Roads. When news of this action reached Britain in the spring of 1862, a wave of popular critical reaction swept over Whitehall. It was only by pointing out the brown-water limits of the Monitor that Palmerston in the House of Commons and the Duke of Somerset in the House of Lords were able to defer any serious lack of public confidence in national defense by sea.

During the Trent crisis “the only Danger” Palmerston could conceive from the Union Navy “would arise from their having armed their vessels with very heavy guns throwing large Shells, and being therefore Gun for Gun probably stronger than ours of similar classes.” The Warrior and her sisters, he assumed, would “checkmate” these. 11 The Monitor altered the equation. “Only think of our position,” warned Foreign Secretary Lord Russell to Palmerston, “if in case of the Yankees turning upon us they should by means of iron ships . . . renew the triumphs they achieved in 1812–13 by means of superior size and weight of metal.” 12

Thus, following news of the 17 September Battle of Antietam and President Lincoln’s subsequent Emancipation Proclamation, the strategic problem of the Monitor and her sisters under construction seriously complicated the idea of war with the United States. During the previous December, Britain was single-handedly ready to “iron the smile out of their face,” wrote Secretary of State for War Sir George Cornewall Lewis. By the following October, nothing less than a unified front of five major European powers would be required, Russell finally admitted, to ensure that Washington would not go through with its standing threat of war if Europe recognized the Confederacy. Lewis had meanwhile warned his cabinet colleagues that “the small iron-cased steamers of America,” while “not sea-going ships, would prove destructive in the ports and rivers.” 13 This stood as the most important strategic and diplomatic victory of the Union during the Civil War, as Uncle Sam finally stared down the “Mistress of the Seas.”

The Northern press, as could be expected, took no end of pleasure from this overseas reaction to the Battle of Hampton Roads. Scientific American reversed its previous insistence on oceangoing Warriors and declared the Monitor more of the new ideal. Harper’s Weekly depicted the Monitor literally lecturing foreign powers how to build proper ironclad warships, showing up Johnny Bull in the proverbial contest of toy boats on ponds, and forcing the British Lion to change its tune over possible intervention. 14 It seemed, in those golden days and weeks following her debut, that anything indeed was possible.

In fact, the Monitor was capable of achieving very little—especially against forts. On 15 May 1862, she attempted to force her way up the James River and place the Confederate capital of Richmond under her guns. A handful of cannon on the river bluffs using plunging fire, combined with obstructions blocking the river, were enough to drive off the Monitor and leave her companion ironclad—Bushnell’s Galena —riddled with holes and casualties.

Yet despite her commanding officer’s misgivings, Gustavus Fox insisted that the newer monitors, in sufficient numbers, might smash their way into even the most heavily guarded Southern ports, which would then be left with the stark choice of surrender or bombardment. This might have worked had not the Confederates learned that torpedoes, combined with forts and obstructions, were often enough to outscare the enemy in his terrible new engines of war. Turret ships might deliver 15-inch guns through gauntlets of fire and sink any enemy warship, armored or not, they encountered. But monitors were just as susceptible to underwater threats as the Cairo , or the Warrior , and much more prone to sinking if actually damaged, having little reserve buoyancy.

Fox’s plans quickly unraveled on 7 April 1863. That’s when Rear Admiral Samuel Francis DuPont’s squadron of seven Passaic -class monitors, the powerfully armed broadside ironclad New Ironsides , and the weakly armed and armored Keokuk was ingloriously repulsed when it attempted to silence Charleston’s outer forts. No determined effort had been made to sweep the main channel of obstructions or torpedoes, leaving the monitors floundering about in a perfect kill zone, discharging 128 shots while absorbing the bulk of some 2,209 Confederate rounds. 15 Amazingly, only one monitor sailor was killed in this terrible maelstrom of fire. The Keokuk , on the other hand, was so riddled with penetrative hits she sank the next day, while the unwieldy New Ironsides was obliged to anchor out of the thick of the fight to avoid running aground.

What the Union Navy actually needed in its combined operations against Charleston were more broadside ironclads, such as the New Ironsides (drawing 16 feet of water) if not the Warrior (drawing 26). At the very least, a half a dozen iron-armored steam-batteries like those used by France during the Crimean War (drawing nine feet) might have likewise overpowered Forts Wagner, Moultrie, and Sumter, while the channel obstructions were swept. Union firepower could then be brandished before the “Heart of Rebeldom.” 16

Perhaps this fateful, strategic dichotomy of monitor vs. broadside ironclad was best summed up by Union Rear Admiral David Dixon Porter during the massive combined operations against Fort Fisher, North Carolina, near the close of the Civil War:

The [double-turret monitor] Monadnock is capable of crossing the ocean alone (when her compasses are once adjusted properly), and could destroy any vessel in the French or British navy, lay their towns under contribution, and return again (provided she could pick up coal) without fear of being followed. She could certainly clear any harbor on our coast of blockaders in case we were at war with a foreign power. . . . Compared with the Ironsides , [the monitors’] fire is very slow, and not at all calculated to silence heavy batteries, which require a rapid and continuous fire to drive men from the guns; but they are famous coadjutors in a fight, and put in the heavy blows which tell on casemates and bombproofs. 17

Veteran Union ironclad skipper Commodore John Rodgers also believed that “the Monitor class and the Ironsides class are different weapons, each having its peculiar advantages; both needed to an iron-clad navy, both needed in war.” 18

Nevertheless, as ironclad killers, the monitors reigned supreme. Confederate armored rams that ventured out to challenge them were routinely forced to retire or surrender within minutes. On 17 June 1863, heartened by the repulse of DuPont’s ironclad squadron before Charleston, the CSS Atlanta sallied forth to challenge the blockade of Savannah. Waiting for her were two Passaic -class monitors, the Weehawken and Nahant . At 300 yards a shot from one of the lead monitor’s 15-inch guns blasted a hole through the Atlanta ’s sloping 4-inch iron shielding, spraying the gun deck with wooden splinters and iron fragments and knocking out most of the crew there. The ram surrendered shortly afterward. 19 Already caught in a losing battle at Mobile Bay, the CSS Tennessee ’s fate was sealed when the Manhattan ’s 15-inch guns “admitted daylight through our side, where, before . . . there had been over two feet of solid wood, covered with five inches of solid iron,” according to one Confederate survivor. 20

The London Times demurred that these examples were hardly comparable to what could be expected in a U.S.–Royal Navy encounter. Confederate casemates had laminated armor plates—though inclined at least 45 degrees to the horizon—and the latest experimental British Armstrong guns would have accomplished even more damage in less time. At any rate, the American Army & Navy Journal responded that “those iron-clads which the Times has handled so severely, the Monitor Monadnock among the rest, are intended for coast and harbor defense. It is not proposed to send these vessels after the [Royal Navy’s] Bellerophons or Minotaurs , but at the same time it may not be prudent to send these unwieldy craft after them.” 21

Unknown to the American press, the Admiralty had indeed already come to same conclusion long before. Rear Admiral Robinson warned Somerset and First Naval Lord Sir Frederick Grey that “very little damage it is apprehended could be done by Great Britain to the coastal towns of America by hostile operations. They are well defended now by land fortifications and the war with the South has called into existence a large fleet of vessels adapted for purposes of defence.” 22

Within months of the Civil War ending, the Navy Department proved willing to extend this strategic armored shield, the ultimate fulfillment of the Monroe Doctrine, as far as technologically possible. To send a potent message to Napoleon III’s occupying forces in Mexico while bolstering California’s defenses, the Monadnock was sent to San Francisco via Cape Horn. Along the way she was prepared to sink the French-built, iron-hulled broadside ironclad Numancia —the pride of the Imperial Spanish Navy—which threatened Valparaiso (see “ Chilean Standoff ,” June 2011, pp. 58–65). No sooner had the Monadnock reached her destination than her sister ship Miantonomoh was anchoring off Portsmouth.

In 1866 a young English aristocratic traveler to America recalled how “General Grant’s first words to me at Washington were: ‘Glad to meet you. What have you seen?’ ‘The Capitol.’ ‘Go at once and see the Monitors.’ He afterward said to me, in words that photograph not only the Monitors, but Grant, ‘You can batter away at those things for a month, and do no good.’” 23 Inasmuch as the vessels had become synonymous with American armored warships, all things safe and secure in everyday life were now “ironclad”—from brands of commercial products to the postwar oath of allegiance.

But they were also victims of their own success. The Union Navy was the greatest purpose-built naval force of the 19th century, but strategic faith in the monitors helped allow the United States to disband its forces wholesale, keeping a fraction of these rusting iron sentinels anchored here and there until European advances in naval guns and armor inevitably doomed them to obsolescence. America likewise no longer need Ericsson or Fox; the former faded into legend, the latter into obscurity.

For his part, Grant concluded his Personal Memoirs in 1885 by warning that however formidable the Civil War had made America it was now manifestly dangerous for the country to be “going on as if in the greatest security, without the power to resist an invasion by the fleets of fourth-rate European powers for a time until we could prepare for them.” That highlighted the need for a new navy for deterrence and commerce protection, and ever-modernized coastal defenses. 24 But as naval historian Craig Symonds opined in 1982, a “good case can be made that the American policy of virtually ignoring the country’s maritime frontiers in the two decades after Appomattox was a reasonable one.” 25

Indeed, for all the posturing of America’s newfound ironclad might by the end of the Civil War—enough to embarrass British “naval supremacy” in 1866 in a way no one could have imagined in 1861—the fact remained that demobilization was an equally important strategic gesture. “We are surrounded by a wall of iron,” proclaimed John Ericsson in March 1865, “within which we intend, unmolested, to develop our national strength.” 26 Reconstruction and railroads were fast becoming the order of the day. And while the U.S. Navy consequently slumbered in its own “Dark Age,” Robert Spencer Robinson, the long-retired controller of the Royal Navy, had to admit in an 1880 article that when considering “England as a Naval Power”—especially in relation to foreign navies—“the United States especially can develop an immense naval force, should circumstances require it.” 27

The British admiral quietly dropped this monumental bomb of historical truth in a footnote.

1. London Times 30 June 30 1866.

2. London Times 16 July 16 1866. It seems more likely Fox made the boast at Spithead than when he was in London the week before.

13. Sir George Cornewall Lewis to Edward Twisleton, 5 December 1861, from Gilbert Frankland Lewis, ed., Letters of the Right Hon. Sir George Cornewall Lewis, Bart. to Various Friends (London: Longmans, Green, and Co., 1870), 406. Russell to Palmerston, 24 October 1862, Palmerston Papers. Secretary for War Sir George C. Lewis, 7 November 1962, Recognition of the Independence of the Southern States of the North American Union , British National Archives (Kew), WO 33/12, 2.

14. Scientific American , 8 November and 11 October 1862. Harper’s Weekly , 10 and 31 May 1862.

15. See the individual battle/damage reports in Official Records of the Union and Confederate Navies in the War of the Rebellion (hereafter ORN ), series 1, vol. 14, 10–24.

Turret vs. Broadside

Following the 9 March 1862 Monitor-Virginia stalemate at the Battle of Hampton Roads, Congress allocated funds for the importation of iron plates from leading English and French manufacturers—which were busy completing orders for the armored warships then under construction throughout Europe. The brutally simple purpose was to test how the new 15-inch Rodman smoothbores for the Army’s coastal forts and Dahlgren guns for the Navy’s monitors might cope with any possible foreign naval intervention in the Civil War.

The plates were backed by up to 24 inches of oak, thoroughly bolted together and then packed against a solid hillside bank of clay (which absorbed much of the force of impact). At close-combat ranges the results confirmed the subsequent experiences between Confederate ironclads, with their angled armor schemes, and Federal monitors: Nothing afloat could resist a projectile weighing more than 400 pounds thrown at even moderate velocity.

A tall broadside of relatively thin armor was inferior to thicker, more concentrated shielding. Likewise, a long row of smaller guns was less likely to inflict damage against an ironclad than fewer guns of much greater individual hitting power.

What complicated the classic debate of “Turret vs. Broadside” was that it was never as simple as raw protection or caliber. Because of the colossal weight of the XV-inch Dahlgren (in excess of 22 tons, with iron carriage), it could only be wielded on a revolving turntable—a steam-rotated gun turret—mounted on the centerline of a vessel. As a result, Civil War monitors radically reconceptualized warships as floating weapons platforms first, and traditional cruisers second; they deliberately forfeited the longer strategic range offered by a full sailing rig in favor of local (coastal) tactical supremacy.

Despite several ingenious mechanical contrivances for operating such monster guns in a confined space with a comparatively small crew, reloading was often agonizingly slow, implying a lower overall volume of sustained fire. While they could quickly devastate enemy ironclads, they could not be expected to silence a fort, for example. The best weapons platform for that role, shore bombardment, was ironically a broadside ironclad such as HMS Warrior . The Miantonomoh , by contrast, was purpose-built to neutralize that threat.